Hypodermic syringe



May 5, 1931. H. K. BROWN HYPODERMIC SYRINGE Filed Dec. 16. 1927 PatentedMay` 5, 1931 Y ire STATES PATENT ori-nice HENRY K. BROWN, OF CHICAGO,ILLINOIS, .ASSIGNOR TO COOK LABORATORIES, ING.,

OF CHICAGO, ILLINOIS, A. CORPORATION OF DELATTARE HYPODERMIC SYRINGEApplication mea December 1e, leer.. seriali No. 240,386.

This invention relates to hypodermic syringes of the kind comprising acartridge Vand cartridge-piercing canula or needle in the annexeddrawings, and will be more particularly pointed out ,in the claimsfollowing this description.

In said drawings:

Fig. 1 is a longitudinal sectional view of a syringe comprising orcontaining the illustrativeY embodiment of the invention;

Fig. 2 is a side elevation of the cartridge embodied in said syringe,the front portion of the cartridge being shown in section;

F ig. 3 is an enlarged sectional Aview of a pierceable stopper in thefore end of said cartridge; and n Fig. 4 is a rear end'view of saidcartridge.

The cartridge embodied in the illustrative syringe comprises a glasstube 1 sealed at its ends by stoppers 2 and 3 and containing anaestheticsolution or other medicament to be dispensed. The stoppers arepreferably` of resilient material such as soft rubber or oth'- ersuitable material or composition. The stopper 2 is to be'pierced by afine canula or hollow needle and to seal around the same, and thestopper 3 is to be pushed inward to expel the fluid through the needle.To secure the stopper 2 in the tube so as to resist relativedisplacement in the cartridge-piercing or fluid-ejecting operations,said stopper is mechanically interlocked with the tube by an annular ribon one of them engaging an annular groove in the other. i stance thetube is shown beaded at 4 to provide a groovel engaging theannularprojection 5 on the stopper 2, whereby the desired interlocking isobtained. As shown, the stopper protrudes substantially beyond the foreend of the glass tube to provide a cushion. By forming the stopper withthe inwardly facing axial cavity 6, the advantage is obtained that theinner tubular end of the stopper is readilyv compressed and facilitatesthe compression of the immediately adjacent portion of the stopper whenforcibly insert- In this iningit'into the tube soas to seal the-rib 5 inY the groove provided-by the bead4. On the other hand, in thefluid-ejecting action the hydrostatic l pressure acting on the annularwall surrounding said recess presses said wall more forcibly against theinterior of theftube, tending totighten-the hold of the stopperandAresisting displacement.

The syringe or injectlon-administeringorganization showny in Fig.l 1comprises said cartridge with meansembodied in this Vinstance in asyringe-like instrument. vReferring to said F ig. 1,'the cartridge ismountedfin vthe holder or tubular-like instrument! body 7 with the foreend of the cartridge seated against the inner side of the head 8, f

and with the rubberstopper 2 impaled upon. and forming a' resilient sealaround the inwardly-protruding end of the double-pointed needle 9. Inoperation, the plunger rod @10 is forced into the cartridge-tube,drawing the piston plug 3 inwardly and forcibly expelling the medicamentsolution through the needle.

InA this action, the'mechanical interlockbetween the stopper 2 and thetube resists tend'-v ency to relative displacement while the protrusionofthe stopper beyond' the end Of the glass tube cushions it against endthrust. The resiliency of the compressed stopper and the hydrostaticpressure action on the interior ofthe tubular part of the .stoppercontribute' with themechanical interlock in the maintenanceof a goodseal. v Y p In' the particular instrument selected for illustration, thehead 8 is detachable, being ecy screwed upon the front end of theinstrument shown fitted in the breech end of the cartridge holderorvinstrumentA barrel, the cartridge being clamped between said gasketand the n, in!

vgroove and thereby mechanically interlocked with the tube, the stopperprotrudingsubstantially beyond the end of said tube to provide acushioning means.

2. A syringe cartridge comprising a straight glass tube beaded near itsfore end, having a sealing stopper of resilient material iitted in thesaid beaded fore end and adapted to be pierced by a needle, and having apiston plug in its opposite end adapted u to be pushed into or throughthe tube to eject the liquid contents through the needle, saidpierceable stopper shaped to iit the bead of the tube, being otherwisecylindrical and of substantially uniform diameter and having cylindricalportions iitted in the tube both behind and in front of the bead of thetube, and the cylindrical portion of said stopper in front of the beadprojecting substantially beyond the fore end of the tube to provide acushioning means.

3. A syringe cartridge comprising a sealed medicament container having aclosure to be pierced by and seal around a needle and constructed tohave the interior volume of the cartridge reduced for ej ecting thefluid contentsA through the needle, said cartridge embodying asubstantially straight glass tube formed near its fore end with anannular bead providing an interior annular groove and said sealingclosure comprising a cylindrical stopper of resilient material formedintermediate its ends with an annular rib engaging said groove, wherebythe stopper is interlocled with the tube to resist relative displacementin either direction between the tube and stopper during theluid-ejecting operation. y

In testimony whereof, I have signed my name to this speciication.

HENRY K. BROWN.

